For everyone not knowing how to install the Vehicles:
1. Go to
Grand Theft Auto V/mods/update/x64/dlcpacks/patchdayXng/dlc.rpf/x64/levels/gta5/vehicles.rpf
using OpenIV
(The X is for the patchday number. use the latest patchday for example patchday24ng)
(if you don't have a mods folder, create one. If you don't have the update folder in your mods folder, copy the updates folder from your GTAV directory into the mods folder)
2. Drag and drop the vehicle files to the archive (don't forget using Edit Mode)
3. Drag and drop the .xml files in the ELS folder to:
Grand Theft Auto V/ELS/pack_default
4. Have fun!